1. Field of the Invention
This invention relates generally to door latch sets and relates more particularly to an interior door latch assembly having relatively few working parts therein.
2. Description of the Prior Art
As is well known in the art, various types of door latch sets are presently available. However, several problems and difficulties are encountered in installing and maintaining these devices.
A conventional door latch set is designed to be installed by drilling a large hole through the free end of the door, cutting or gouging a slot for coacting with the bolt mechanism, and then boring or gouging an opening on the door frame opposite the bolt mechanism. A strike plate which engages the bolt in the closed position is fastened to the door frame over this opening.
To install this type of mechanism requires a considerable amount of labor, special tool of several kinds, and special skills. This results in the disadvantage that a skilled carpenter must install the latching assemblies and must take great care to determine the exact location in the door and door frame for the various holes and recesses.
Small errors result in doors that will not latch properly. Large errors result in ruined doors.
Various approaches have been taken to solve these problems. Some of them are illustrated in U.S. Pat. No. 258,431, U.S. Pat. No. 921,711, U.S. Pat. No. 2,003,731, U.S. Pat. No. 2,194,601, U.S. Pat. No. 2,617,287 and U.S. Pat. No. 3,608,939.
None of these examples of the prior art satisfactorily solve the problems of providing a low cost, simple means of installing an interior door latch whose mating parts are within the door end and the door frame.